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Phytoplasma induced free-branching in commercial poinsettia cultivars

Nature Biotechnologyvolume 15pages178182 (1997) | Download Citation



Free-branching poinsettia cultivars that produce numerous axillary shoots are essential for propagating desirable multi-flowered poinsettias (Euphorbia pulcherrima Wild. Klotz). For more than a decade, a biological agent has been suspected to cause free-branching in poinsettias. Attempts to identify the branching agent have failed. Isolation of the pathogen was accomplished using a living host and it was concluded that an unculturable phytoplasma is the cause of free-branching in poinsettias. This is the first reported example of a pathogenic phytoplasma as the causal agent of a desirable and economically important trait.

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  1. Ing-Ming Lee: Corresponding author (e-mail:


  1. Molecular Plant Pathology Laboratory, USDA ARS, Beltsville, MD, 20705

    • Irena M. Bartoszyk
    •  & Dawn E. Gundersen-Rindal
  2. Ball FloraPlant, West Chicago, IL, 60185-2698

    • Michael Klopmeyer
    • , Tau-San Chou
    • , Karen L. Thomson
    •  & Robert Eisenreich


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